Conventionally, an endoscope apparatus including an endoscope, a light source device, and the like has been widely used in a medical field and the like. The endoscope apparatus in the medical field, in particular, is mainly used for the purpose of observation and the like in a living body as a subject to be inspected by an operator or the like. As the light source device used in the above-described endoscope apparatus, there is proposed a light source device for endoscope in Japanese Unexamined Patent Application Publication No. 2002-238846, for example.
In addition, commonly known observation by using the endoscope apparatus in the medical field includes, for example, in addition to normal observation in which a subject in a living body is irradiated with white light to pick up an image of the subject generally the same as that in observation with the naked eye, narrow band observation (NBI: Narrow Band Imaging) in which an image of blood vessels and the like on a mucosa surface layer in a living body can be picked up with high contrast compared with the normal observation, by performing observation irradiating a subject with narrow-band light having a narrower wavelength band than illumination light in the normal observation.
A light source device for endoscope proposed in Japanese Unexamined Patent Application Publication No. 2002-238846 includes three LEDs, that is, R (red), G (green), and B (blue) LEDs, an LED control circuit for controlling light emission intensity of each of the three LEDs, and a color adjustment switch capable of adjusting the light emission intensity of each of the three LEDs, through the LED control circuit, by an operation by an operator or the like. With the above-described configuration, the light source device for endoscope proposed in Japanese Unexamined Patent Application Publication No. 2002-238846 is capable of freely adjusting the color of an image of a subject in a living body picked up by the endoscope, as needed.
However, the light source device for endoscope proposed in Japanese Unexamined Patent Application Publication No. 2002-238846 does not include color adjustment means for adjusting the color of the subject image which supports narrow band observation. Therefore, in the observation using the light source device for endoscope proposed in Japanese Unexamined Patent Application Publication No. 2002-238846, an operator or the like is required to perform narrow band observation using a dedicated device such as another light source device and the like, for example. As a result, there is a problem that the time period to be spent on the observation of a subject in a living body becomes longer.
The present invention has been achieved in view of the above-described circumstances, and the object of the present invention is to provide a living body observing apparatus capable of reducing the time period to be spent on observation of a subject in a living body.